Filament power supply remote control and reset protection circuit

Abstract

The utility model discloses a filament power supply remote control and reset protection circuit, which comprises an enabling end light signal receiver, a relay K2 and a filament power supply power module, and is characterized in that the input end of the enabling end light signal receiver is used for receiving an enabling control signal transmitted by an optical fiber; a power supply is connected to an output positive electrode of the enabling end optical fiber receiver through a coil of a relay K2, and a grounding end of the enabling end optical fiber receiver is grounded through a resistor R1; and a normally open contact K21 of the relay K2 is connected in series in an enabling control loop of the filament power supply power module and is used for controlling the enabling work of the filament power supply power module. The utility model has the advantages that the circuit structure is simple and reliable, and enabling work and reset control of a filament power supply can be remotely controlled; meanwhile, over-current and under-current can be adjusted and controlled, and the safety of the filament power supply is protected.

Description

Technical Field

[0001] The utility model relates to the field of filament power supply control and protection, in particular to a filament power supply remote control and reset protection circuit. Background Art

[0002] The filament power supply is a special type of power supply, which is mainly used to provide a stable current to the filament to make it heat up and emit electrons. This is particularly critical in equipment such as X-ray machines and electron beam welders. For example, the patent application number is 201710857961.8, which is an X-ray filament power supply device based on laser energy supply technology, including a host computer, a laser emission module, an energy supply optical fiber, a photoelectric conversion module, a DC / DC power supply module, a measurement power supply module, a filament voltage and current measurement module, a voltage measurement transmission optical fiber, a current measurement transmission optical fiber, an optical fiber receiving module, a CPLD module, a high-voltage oil tank and a filament; the photoelectric conversion module, the DC / DC power supply module, the measurement power supply module, and the filament measurement module are placed in the high-voltage oil tank to achieve insulation, sealing and heat dissipation; the photoelectric conversion module, the DC / DC power supply module, and the measurement power supply module are all added with heat sinks and fixed to the side wall of the high-voltage oil tank. This patented technology can well meet the use requirements of X-ray filament power supplies.

[0003] This type of filament power supply equipment may have high voltage or radiation in the working scene, and the equipment is relatively expensive, so remote control and fault protection of the product are particularly important. In this case, if a fault occurs during operation and is not discovered in time, the components may be damaged at the least, or the filament may be burned out and cause significant losses. At this time, a simple circuit design is needed to achieve remote control of the constant current source switch reset, and to respond in time to cut off the input when a fault occurs, to protect the circuit safety and avoid major losses. However, the existing technology often has defects such as complex circuits and inadequate protection in the remote control of filament power supplies. Utility Model Content

[0004] The purpose of the utility model is to overcome the shortcomings of the prior art and provide a filament power supply remote control and reset protection circuit, which uses optical fiber to receive enable and reset signals to control the operation of the equipment and reset after fault protection, uses current control signals to control the output current, and uses a dual-channel comparator to achieve overcurrent and undercurrent fault protection, wherein the overcurrent fault protection is locked and cannot be self-recovered, and the undercurrent fault can be recovered by increasing the current control reference. The three indicator lights can display the three working states of the power supply in real time, so that the user can understand the fault information and deal with the fault. Finally, the output current of the filament power supply as well as the fault protection and reset functions are remotely controlled through two optical fibers and a current control signal.

[0005] In order to achieve the above-mentioned purpose, the technical solution adopted by the utility model is: a filament power supply remote control and reset protection circuit, including an enable end optical signal receiver, a relay K2, and a filament power supply power module, wherein the input end of the enable end optical signal receiver is used to receive an enable control signal transmitted via an optical fiber; the coil of the relay K2, the capacitor C2, and the resistor R1 are connected in series, one end of which is connected to a power supply, and the other end is grounded; the two output terminals of the enable end optical fiber receiver are respectively connected to the two ends of the capacitor C2; the normally open contact K21 of the relay K2 is connected in series in the enable control loop of the filament power supply power module, and is used to control whether the filament power supply power module is enabled or not.

[0006] The circuit also includes a comparator N1A, wherein an IN+ input terminal of the comparator N1A is used to input an overcurrent signal, an IN- input terminal of the comparator N1A is connected to an anode of a diode V2, a cathode of the diode V2 leads to a FAULT terminal, and the FAULT terminal is connected to a ground terminal of two output terminals of the enabled optical fiber receiver.

[0007] The circuit further includes a diode V1, wherein an anode of the diode V1 is connected to an output terminal of the comparator N1A, and a cathode of the diode V1 is connected to an IN+ input terminal of the comparator N1A.

[0008] The circuit further includes a comparator N1 B, wherein an IN+ input terminal of the comparator N1 B is input to a reference voltage; an IN- input terminal of the comparator N1 B is input to a current control signal; an output terminal of the comparator N1 B is connected to an anode of a diode V3, a cathode of the diode V3 is connected to a FAULT terminal, and the FAULT terminal is connected to a ground terminal of two output terminals of the enabled optical fiber receiver.

[0009] The circuit also includes a reset end optical receiver, a relay K1, and a capacitor C1. The input end of the reset end optical fiber receiver inputs a reset signal through an optical fiber; the relay K1 and the capacitor C1 are connected in series, one end of which is connected to a power supply and the other end is grounded; the two output ends of the reset optical fiber receiver are respectively connected to the two ends of the capacitor C1; and the normally closed contact K11 of the relay K1 is connected in series in the power supply circuit of the comparator N1A.

[0010] One end of the normally closed contact K12 of the relay K1 is connected to the power supply, and the other end is connected to the normally open contact K21 of the relay K2. One end of the normally open contact K21 of the relay K2 leads to an enable signal terminal connected to the filament power supply module.

[0011] One end of the normally open terminal K22 of the relay K2 is connected to the normally closed contact K12, and the other end leads to an enabling lamp terminal for connecting to the enabling lamp.

[0012] An undercurrent lamp terminal is led out between the diode V3 and the comparator N1B, and is used to be connected to an undercurrent lamp.

[0013] An overcurrent lamp terminal is led out between the output terminal of the comparator N1A and the anode of the diode V2 , and is used to be connected to an overcurrent lamp.

[0014] The utility model has the advantages that the circuit structure is simple and reliable, and the enabling operation and reset control of the filament power supply can be realized by remote control; at the same time, overcurrent and undercurrent can be regulated and controlled to protect the safety of the filament power supply. BRIEF DESCRIPTION OF THE DRAWINGS

[0015] The following is a brief description of the contents expressed in the drawings of the present invention and the symbols in the drawings:

[0016] Figure 1 The utility model is a circuit schematic diagram of the control and protection circuit. DETAILED DESCRIPTION

[0017] The specific implementation of the present invention will be further explained in detail below by describing the optimal embodiment with reference to the accompanying drawings.

[0018] The purpose of the utility model is to provide a remote control protection reset circuit, which uses optical fiber to receive enable and reset signals to control the operation of the device and reset after fault protection, uses current control signals to control the output current, and uses dual comparators to achieve overcurrent and undercurrent fault protection, wherein the overcurrent fault protection is locked and cannot be self-recovered, and the undercurrent fault can be recovered by increasing the current control reference. The three indicator lights can display the three working states of the power supply in real time, so that the user can understand the fault information and deal with the fault. Finally, the output current, fault protection and reset functions of the filament power supply can be remotely controlled through two optical fibers and a current control signal.

[0019] like Figure 1 As shown, a circuit structure of a filament power supply remote control protection reset circuit includes two optical fiber receivers D1 and D2 and two comparators N1A and N1B; wherein D1 is used to receive a reset signal, and D2 is used to receive an enable signal; both optical fiber receivers D1 and D2 are implemented using HFBR-2412 chips. The input ends of D1 and D2 input reset signals and enable signals respectively through optical fibers; pins 2 of D1 and D2 are both power terminals for connecting to a +5V power supply, pins 3&7 are both ground pins, and pin 6 is an output pin. Pin 6 of the optical fiber receiver D1 is connected to a +12V power supply via the coil of relay K1, pins 3&7 of D1 are grounded, and capacitor C1 is connected between pins 6 and 3&7 of the optical fiber receiver D1 to achieve filtering protection, etc.

[0020] Pin 2 of the optical fiber receiver D2 is connected to a +5V power supply, pins 3&7 are grounded via resistor R1, and pin 6 is connected to a +12V power supply via the coil of relay K2; capacitor C2 is connected between pins 6 and 3&7 of the optical fiber receiver D2 to realize filtering protection and other functions. The +12V power supply is connected to the power supply end of the comparator N1A via the normally closed contact K11 of relay K1; the +12V power supply is connected to one end of the normally open contact K21 and one end of the normally open contact K22 of relay K2 via the normally closed contact K12 of relay K1, and the other end of the normally open contact K21 leads to an enable signal terminal for connecting to the enable control end of the filament power module, for controlling whether the filament power module is enabled or not, thereby controlling the operation of the filament power supply. The other end of the normally open contact K22 is connected to an enable light for displaying the enable status.

[0021] The I N+ of the comparator N1A inputs the overcurrent signal. The overcurrent signal can be collected and converted by the sensor inside the filament power supply to form an overcurrent signal and sent to the +IN terminal of the comparator N1A; the -IN terminal of the comparator N1A inputs the reference voltage; the output end of the comparator N1A is connected to the anode of the diode V2, and the cathode of the diode V2 leads to the FAULT terminal, and the FAULT terminal is connected to the 3&7 ground output terminals of D2; the output end of the comparator N1A is connected to the anode of the diode V1, and the cathode of the diode V1 is connected to the +in terminal of the comparator N1A. The output end of the comparator N1A leads to the overcurrent lamp terminal for connecting to the overcurrent lamp.

[0022] The reference voltage is input to the +IN terminal of comparator N1B, and the control current signal is input to the -IN terminal of comparator N1B; the output of comparator N1B is connected to the anode of diode V3, and the cathode of diode V3 is connected to the FAULT terminal. The output of comparator N1B leads to the undercurrent lamp terminal for connecting to the undercurrent lamp. The control current signal is a control signal corresponding to the output current of the filament power supply. This control signal is simultaneously input to the filament power supply to adjust the output of the filament power supply, and is also input to this circuit. If the output current of the filament power supply is undercurrent, it means that the control current signal is insufficient and needs to be increased. When the filament current is increased, the filament current is no longer undercurrent. At this time, the output signal of the comparator of this circuit will also become low, thereby solving the undercurrent fault.

[0023] The working principle of the circuit in this embodiment is: the circuit has three input signals: two optical fiber signals (enable, reset), and a constant current source output current control signal; the output includes three status indicator light signals (enable light, overcurrent light, undercurrent light) and an enable signal.

[0024] Control part: A relay is connected behind each of the two fiber optic receivers. When the fiber optic receives a signal, the output end of the fiber optic receiver is turned on. The 12V power supply is connected to the enable signal through the normally closed contact of relay K1 and the normally open contact of relay K2. When the fiber optic D2 receiver receives the enable signal, the K2 relay is energized. At this time, the enable signal has a 12V output, and the power part behind the control works normally, and the enable light is on.

[0025] Protection part: The protection part protects the circuit through the FAULT signal. When the FAULT is high, the relay K2 does not conduct because it cannot reach the conduction voltage, and there is no enable signal to the power circuit. At this time, the power supply cannot work properly. The 2nd and 5th pins of the dual comparator N1 are connected to the reference signal. When the overcurrent signal is received, the 1st pin of N1 will output a high level to pull the FAULT high through the V2 diode. Since the constant current source may cause serious losses when it is overcurrent, positive feedback is added through V1. During overcurrent protection, it will continue to output a high level, the power supply is locked, and the overcurrent light is always on; undercurrent protection is controlled by current control reference. When the reference voltage is too small, the 7th pin of N1 will output a high level, causing the relay K2 to fail to conduct, the enable signal cannot reach the power part, the power supply does not work, and the undercurrent light is on. The reference signal can be increased by increasing the current control until the threshold is reached, and the power supply can work normally.

[0026] Reset part: When the optical fiber receiver N1 receives the reset signal, the relay K1 is energized, the enable signal is disconnected, and the power supply part of the comparator N1 is also disconnected, and the FAULT signal disappears. When the reset signal ends, the power supply can work normally again, so that a remote optical signal can control the reset and restart of the power supply without the need to power off and restart the device.

[0027] The embodiment of the present application uses a simple circuit design to achieve remote control of the constant current source switch reset, and to respond promptly to cut off the input when a fault occurs, thereby protecting the circuit safety and avoiding significant losses. Optical fibers are used to receive enable and reset signals to control the operation of the equipment and reset after fault protection, and current control signals are used to control the output current. A dual-channel comparator is used to achieve overcurrent and undercurrent fault protection, wherein the overcurrent fault protection is locked and cannot be self-recovered, and the undercurrent fault can be recovered by increasing the current control reference. The three indicator lights can display the three working states of the power supply in real time, so that users can understand the fault information and deal with the fault. Finally, the output current of the filament power supply as well as the fault protection and reset functions are remotely controlled through two optical fibers and a current control signal.

[0028] Obviously, the specific implementation of the present invention is not limited to the above-mentioned methods. As long as various non-substantial improvements are made using the method concept and technical solution of the present invention, they are all within the protection scope of the present invention.

Claims

1. A filament power supply remote control and reset protection circuit, characterized in that: It includes an enable end optical signal receiver, a relay K2, and a filament power supply module. The input end of the enable end optical signal receiver is used to receive an enable control signal transmitted via an optical fiber; the power supply is connected to the output positive pole of the enable end optical receiver via the coil of the relay K2, and the ground end of the enable end optical fiber receiver is grounded via a resistor R1; the normally open contact K21 of the relay K2 is connected in series in the enable control loop of the filament power supply module to control whether the filament power supply module is enabled or not.

2. A filament power supply remote control and reset protection circuit as claimed in claim 1, characterized in that: The circuit also includes a comparator N1A, wherein the IN+ input terminal of the comparator N1A is used to input an overcurrent signal, the IN- input terminal of the comparator N1A is connected to the anode of the diode V2, the cathode of the diode V2 leads to a FAULT terminal, and the FAULT terminal is connected to a ground terminal of two output terminals of the enabled optical fiber receiver.

3. A filament power supply remote control and reset protection circuit as claimed in claim 2, characterized in that: The circuit further includes a diode V1 , wherein an anode of the diode V1 is connected to an output terminal of the comparator N1A, and a cathode of the diode V1 is connected to an IN+ input terminal of the comparator N1A.

4. A filament power supply remote control and reset protection circuit as claimed in claim 1, characterized in that: The circuit further includes a comparator N1 B, wherein an IN+ input terminal of the comparator N1 B is input to a reference voltage; an IN- input terminal of the comparator N1 B is input to a current control signal; an output terminal of the comparator N1 B is connected to an anode of a diode V3, a cathode of the diode V3 is connected to a FAULT terminal, and the FAULT terminal is connected to a ground terminal of two output terminals of the enabled optical fiber receiver.

5. A filament power supply remote control and reset protection circuit as claimed in claim 2, characterized in that: The circuit also includes a reset end optical receiver, a relay K1, and a capacitor C1. The input end of the reset end optical fiber receiver inputs a reset signal through an optical fiber; the relay K1 and the capacitor C1 are connected in series, one end of which is connected to a power supply and the other end is grounded; the two output ends of the reset optical fiber receiver are respectively connected to the two ends of the capacitor C1; and the normally closed contact K11 of the relay K1 is connected in series in the power supply circuit of the comparator N1A.

6. A filament power supply remote control and reset protection circuit as claimed in claim 5, characterized in that: One end of the normally closed contact K12 of the relay K1 is connected to the power supply, and the other end is connected to the normally open contact K21 of the relay K2. One end of the normally open contact K21 of the relay K2 leads to an enable signal terminal connected to the filament power supply module.

7. A filament power supply remote control and reset protection circuit as claimed in any one of claims 2 to 6, characterized in that: One end of the normally open terminal K22 of the relay K2 is connected to the normally closed contact K12, and the other end leads to an enabling lamp terminal for connecting to the enabling lamp.

8. A filament power supply remote control and reset protection circuit as claimed in any one of claims 1 to 6, characterized in that: An undercurrent lamp terminal is led out between the diode V3 and the comparator N1 B, and is used to be connected to an undercurrent lamp.

9. A filament power supply remote control and reset protection circuit as claimed in claim 2, characterized in that: An overcurrent lamp terminal is led out between the output terminal of the comparator N1A and the anode of the diode V2 , and is used to be connected to an overcurrent lamp.

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